java 空格替换%20
public String replaceSpace(StringBuffer str2) { StringBuffer str4 = new StringBuffer(); int length=str2.length(); char []str3=str2.toString().toCharArray(); for(int i=0;i<length;i++) { if(str3[i]!=' ') { str4.append(str3[i]); } else{ str4.append("%"); str4.append("2"); str4.append("0"); } } //str4.append("\0"); return str4.toString(); }